Abaixo está uma instrução que descreve uma tarefa de geração de SQL, combinada com uma entrada que fornece mais contexto sobre os esquemas de tabela disponíveis. Escreva o código SQL que responda adequadamente à solicitação
 ###Instrução: Qual 1º Quadro U15 teve um 3º VIII Aberto da BBC e um 3º VIII U16 da BBC?
 ###Tabelas: CREATE TABLE installations (installations_id AUTO_INCREMENT PRIMARY KEY, Name VARCHAR, Park VARCHAR, Country VARCHAR, Inversions INT, Opened VARCHAR, Status VARCHAR) CREATE TABLE sunderland_a.f.c_goals (sunderland_a.f.c_goals_id AUTO_INCREMENT PRIMARY KEY, Date VARCHAR, Venue VARCHAR, Opposition VARCHAR, Score VARCHAR, Competition VARCHAR) CREATE TABLE t (t_id AUTO_INCREMENT PRIMARY KEY, Player VARCHAR, No.(s) VARCHAR, Height in Ft. VARCHAR, Position VARCHAR, Years for Rockets VARCHAR, School/Club Team/Country VARCHAR) CREATE TABLE winning_head_of_the_river_championship_events (winning_head_of_the_river_championship_events_id AUTO_INCREMENT PRIMARY KEY, Crew INT, Open 1st VIII VARCHAR, Open 2nd VIII VARCHAR, Open 3rd VIII VARCHAR, U16 1st VIII VARCHAR, U16 2nd VIII VARCHAR, U16 3rd VIII VARCHAR, U15 1st Quad VARCHAR, U15 2nd Quad VARCHAR, U15 3rd Quad VARCHAR, U15 4th Quad VARCHAR, U15 5th Quad VARCHAR, U15 6th Quad VARCHAR) CREATE TABLE employment (employment_id AUTO_INCREMENT PRIMARY KEY, Employment Area VARCHAR, October 2010 VARCHAR, October 2011 VARCHAR, October 2012 VARCHAR, Net change VARCHAR)  
SELECT U15 1st Quad FROM winning_head_of_the_river_championship_events WHERE Open 3rd VIII = bbc AND U16 3rd VIII = bbc